1. Field of the Invention
The invention is directed to an improved measuring instrument for contactless detection of an angle of rotation including a magnetically nonconductive rotor supporting a magnet and a stationary magnetically sensitive element for generating a measurement signal.
2. Description of the Prior Art
In one known measurement instrument described for example in DE 197 53 775.8 A1, flux conducting parts of magnetically conductive material have been used, among other elements, for orienting the lines of magnetic flux. However, this makes these measuring instruments relatively large, and only conditionally can they be built into measurement systems. Also, in this embodiment, it is not possible to vary the slope of the linear portions of the measurement curve sufficiently.
To overcome these problems, a novel measuring instrument for contactless detection of an angle of rotation has a rotor on which a magnet is disposed and also has a magnetically sensitive element for generating a measurement signal. This rotor comprises magnetically nonconductive material, and the magnet is embodied in planar form and is disposed parallel to a plane that passes through the axis of the rotor. Furthermore, the polarization of the magnet is diametrically opposite the axis. In this measuring instrument, no flux parts are used. Moreover, the complexity of assembly of this measuring instrument is reduced sharply. On the other hand, in this measuring instrument, the linear region of the measurement curve cannot exceed 180°.